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Topic: Raw milk safety (Read 6728 times)

I start using raw mik and i am quite concern about safety.My milk source is good and i am keeping cleaning rules.I will use the raw milk for semi firm/firm cheese only. (gouda, swiss, romano, tomme...).I read that 60 days aging in not enough to kill all bad bacteria so myquestion is: wil longer againg time, like 90 days will make thecheese totaly safe ?

Here in The Netherlands it's easy to buy raw cow and goat milk. I make all kinds of cheese with raw milk and the only precaution that I take is to warn women who are eating my cheese that cheeses from raw milk that are younger than 60 days might be dangerous to pregnant women. Besided of course the normal cleansing of all equipment I use and the area where I make my cheese...

60 days is a rule of thumb, only way to garantee saftely is have the milk and cheeses analyzed which is obviously not cost feasable for a non commerical dairy\your avarage home cheesemaker.So in essence, we're risking it and managing the risks to reduce possibility of sickness. (sourcing clean milk from healthy animals, using proper cheesemaking techniques like quick acidification using cultures which reduces food available for spoilage growth, making the cheese quickly after milking or rapidly cooling it for storage)

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Amatuar winemaker,baker, cook and musician not in any particular order.

In both Canada and the US, raw milk cheese must be aged for a minimum of 60 days, which allows all pathogenic bacteria to be killed--but does not affect enterotoxins from some of those pathogens. It is true that raw milk cheeses consumed younger than that, produced with strict sanitation, are found all over the world and, for the most part, have not been a concern--and most cheese experts insist that raw milk is essential for maximum flavor. That being said, raw milk safety is a major concern for those who are professionally associated with its production (as in the animal health and science field, dairy science) and handling. Pasteurization is the ONLY means to ensure milk (and cheese younger than 60 days) safety.

Although raw milk cheese safety is a country-wide legal issue, raw milk sales are managed by the individual States in the US, each having its own policy. Here in California, we have had recent recalls of raw milk from large dairies due to serious bacterial contaminants found in marketed milk--and they have also occurred in other states too. I don't want to get into the 'politics' of drinking raw milk as people who do so routinely tend to feel as strongly about the practice as those who advocate pasteurization. I am married to a retired professor of ruminant physiology who believes Louis Pasteur to be the single person who most affected modern human health, as pasteurization has probably saved more lives than any other health advance. I own dairy goats and pasteurize all milk, whether used for drinking or cheese making. And I know how careful I am with milking sanitation, yet also know the risks of not pasteurizing.

I had a surgery nurse a couple of years ago who contracted Brucellosis from blood spatter when doing routine blood work on a university student from Mexico who had eaten raw milk cheese and came back from his school break very sick. The nurse became CDC (Centers for Disease Control) Brucellosis case #67.

which allows all pathogenic bacteria to be killed--but does not affect enterotoxins from some of those pathogens.

Modern studies have shown this to be false. Risk vector from load, aging conditions, microbiological ecosystem, and cheese profile all affect rate of lysis and pathogenic viability. Viable pathogens have been recovered from cheese is that is 12+ months old without post-contamination.

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Pasteurization is the ONLY means to ensure milk (and cheese younger than 60 days) safety.

Again, legal pasteurization is one tool. Sporification, thermoduric encapsulation, and other mechanisms that bacteria use make 5-log reduction a virtual certainty, but not an absolute one. There are also many other tools available to cheesemakers and from a public health policy perspective, such as thermization, targeted phage use, elevated temperature aging, bacteriocin-producing bacterial adjuncts, rind flora ecologies with associated pathogen targetting, etc.

The bacterial world is much more complex than Pasteur made it out to be.

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Taking an extended leave (until 2015) from the forums to build out my farm and dairy. Please e-mail or PM if you need anything.

Here in California, we have had recent recalls of raw milk from large dairies due to serious bacterial contaminants found in marketed milk--and they have also occurred in other states too.

The basic problem with our food system....whether it's raw milk, hamburger, raw vegetables stuff gets out without apparent testing and then gets recalled. Why wouldn't there be a system in place to test prior to distribution? We seem to put the horse behind the cart altogether too often.

To use recalls of raw milk as a reason (or case #67) to ban raw milk sales, you would also have to advocate the ban of raw beef, vegetables etc etc. It would be better to institute some form of testing process or certification process that is in place prior to distribution.

Organic vegetables are much more likely (due to the use of "alternate" fertilizers) to contain pathogens, and yet the use of chemicals is not preferable for long term maintenance of the soil, not to mention potential side effects of consumption.

Having grown an organic garden for years, I can attest to both the benefits as well as the problems associated with "going organic". Much easier for the small gardener to implement as opposed to a larger farm.

Just an FYI...I personally do not drink raw milk (nor do I drink pasteurized milk), but I do think that those who want to (or to make cheese with it ) should have access. I am also horrified by the growing use of ultra-pasteurization by the dairy industry.

If you are content in the milk and would consume it as milk, then as cheese I am not sure why you worry. Even pasteurized milk can harbour bacteria and then there is still the issue of contamination during your process or storage of the cheese. The only 100% way to be safe from bad milk is NO milk!

In teh restraunt I managed for a number years here in Canada (where Raw milk is absolutley NOT allowed) we had an issue for several months where the milk was sour/chunky when we opened it from the wholesaler! so even that was being comprimised! All you can do is monitor your source and build confidence in it and in your technique and process.

I have found a local supplier for raw milk which I use for all of my cheese that I'm going to age for more than 60 days. Normally that means months more. Anything 60 days and under and I use store bought pastuerized milk.

which allows all pathogenic bacteria to be killed--but does not affect enterotoxins from some of those pathogens.

Modern studies have shown this to be false. Risk vector from load, aging conditions, microbiological ecosystem, and cheese profile all affect rate of lysis and pathogenic viability. Viable pathogens have been recovered from cheese is that is 12+ months old without post-contamination.

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Pasteurization is the ONLY means to ensure milk (and cheese younger than 60 days) safety.

Again, legal pasteurization is one tool. Sporification, thermoduric encapsulation, and other mechanisms that bacteria use make 5-log reduction a virtual certainty, but not an absolute one. There are also many other tools available to cheesemakers and from a public health policy perspective, such as thermization, targeted phage use, elevated temperature aging, bacteriocin-producing bacterial adjuncts, rind flora ecologies with associated pathogen targetting, etc.

The bacterial world is much more complex than Pasteur made it out to be.

It is true that other treatments than heat pasteurization are available, although they cannot all be implemented by all producers, especially those small-time, at-home producers like us, or folks living out in rural areas worldwide. I practice the 'best' sanitation I can at home with my goats, yet wouldn't drink their milk raw and do all I can to ensure safe handling post-milking, including using commercial food surface sanitizer, gloves, etc. All the more reason to be unsure of anyone else's practices, even those whose livelihoods depend on it, because my life (and those I cook for) depend on it.

There have been 2 recalls in just the past 90 days at a very established cheese company here in the USA. This involved several styles of raw milk cheeses, all aged over 60 days, contaminated with Listeria. Nobody has become ill or died or this would be national news. The cheeses were recalled from 6 or 7 states and the Whole Foods chain. I have known this cheesemaker for many years, and I cannot identify them or discuss this any further. I only bring this up as a learning experience that we all should study.

In many ways, this proves that the 60 day rule is not an absolute and as LB points out, there are many variables for survival of pathogens. And as he also points out, there are other tools and techniques for fighting Listeria and other pathogens. For example, Danisco has a series of "protective cultures" that they call HoldBac

Thanks, Sailor. A number of bacteriophages are either being tested or in commercial production for various food uses. I use Natamax on cheeses that are not mold-ripened externally, prior to 'bagging' them. Every little bit helps!

Natamax is good for molds and yeasts, but Danisco does not suggest it for Listeria or coliforms. Yes, there are several interesting phage products either on the market or in development. Most are for the meat market where the majority of Listeria problems occur. The bio-needs are different for dairy products.

It's interesting that Natamax has such a stinky, sulfur smell, but doesn't seem to contribute to any flavor defects.